Structural studies on Pb proteins of the common and variant genetic types will be continued by performing sequential analysis. Monkey Pb proteins will also be studied by sequential analysis for the purpose of a biochemical evolutionary comparison. Possible functions of Pb and Pr-Db proteins will be studied by looking for a relationship between Pb and Pr-Db variant types and the incidence of caries and/or periodontal disease. Attempts will be made to determine cellular and subcellular localization of the Pb proteins using immunofluorescence techniques. Attempts will be made to identify new genetic polymorphisms in human saliva using sensitive protein staining methods, high-voltage starch-gel electrophoresis techniques and radio-labeling of trace protein components followed by autoradiography. We will continue linkage studies of Pb and Pr-Db systems with many known genetic markers in order to assign them to specific linkage groups.